Class TesseractOCRParser

  • All Implemented Interfaces:
    Serializable, Initializable, Parser

    public class TesseractOCRParser
    extends AbstractExternalProcessParser
    implements Initializable
    TesseractOCRParser powered by tesseract-ocr engine. To enable this parser, create a TesseractOCRConfig object and pass it through a ParseContext. Tesseract-ocr must be installed and on system path or the path to its root folder must be provided:

    TesseractOCRConfig config = new TesseractOCRConfig();
    //Needed if tesseract is not on system path
    parseContext.set(TesseractOCRConfig.class, config);

    See Also:
    Serialized Form
    • Field Detail


        public static final Property IMAGE_ROTATION

        public static final Property IMAGE_MAGICK

        public static final Property PSM0_PAGE_NUMBER

        public static final Property PSM0_ORIENTATION
      • PSM0_ROTATE

        public static final Property PSM0_ROTATE

        public static final Property PSM0_ORIENTATION_CONFIDENCE
      • PSM0_SCRIPT

        public static final Property PSM0_SCRIPT

        public static final Property PSM0_SCRIPT_CONFIDENCE
    • Constructor Detail

      • TesseractOCRParser

        public TesseractOCRParser()
    • Method Detail

      • getImageMagickProg

        public static String getImageMagickProg()
      • getTesseractProg

        public static String getTesseractProg()
      • getSupportedTypes

        public Set<MediaType> getSupportedTypes​(ParseContext context)
        Description copied from interface: Parser
        Returns the set of media types supported by this parser when used with the given parse context.
        Specified by:
        getSupportedTypes in interface Parser
        context - parse context
        immutable set of media types
      • parse

        public void parse​(InputStream stream,
                          ContentHandler handler,
                          Metadata metadata,
                          ParseContext parseContext)
                   throws IOException,
        Description copied from interface: Parser
        Parses a document stream into a sequence of XHTML SAX events. Fills in related document metadata in the given metadata object.

        The given document stream is consumed but not closed by this method. The responsibility to close the stream remains on the caller.

        Information about the parsing context can be passed in the context parameter. See the parser implementations for the kinds of context information they expect.

        Specified by:
        parse in interface Parser
        stream - the document stream (input)
        handler - handler for the XHTML SAX events (output)
        metadata - document metadata (input and output)
        parseContext - parse context
        IOException - if the document stream could not be read
        SAXException - if the SAX events could not be processed
        TikaException - if the document could not be parsed
      • hasWarned

        protected boolean hasWarned()
      • warn

        protected void warn()
      • getTesseractPath

        public String getTesseractPath()
      • setTesseractPath

        public void setTesseractPath​(String tesseractPath)
        Set the path to the Tesseract executable's directory, needed if it is not on system path.

        Note that if you set this value, it is highly recommended that you also set the path to (and including) the 'tessdata' folder using setTessdataPath(java.lang.String).

      • getTessdataPath

        public String getTessdataPath()
      • setTessdataPath

        public void setTessdataPath​(String tessdataPath)
        Set the path to the 'tessdata' folder, which contains language files and config files. In some cases (such as on Windows), this folder is found in the Tesseract installation, but in other cases (such as when Tesseract is built from source), it may be located elsewhere.

        Make sure to include the 'tessdata' folder in this path: '/blah/de/blah/tessdata'

      • getImageMagickPath

        public String getImageMagickPath()
      • setImageMagickPath

        public void setImageMagickPath​(String imageMagickPath)
        Set the path to the ImageMagick executable directory, needed if it is not on system path.
        imageMagickPath - to ImageMagick executable directory.
      • getOtherTesseractSettings

        public List<String> getOtherTesseractSettings()
      • setSkipOCR

        public void setSkipOCR​(boolean skipOCR)
      • isSkipOCR

        public boolean isSkipOCR()
      • setLanguage

        public void setLanguage​(String language)
      • getLanguage

        public String getLanguage()
      • setPageSegMode

        public void setPageSegMode​(String pageSegMode)
      • getPageSegMode

        public String getPageSegMode()
      • setMaxFileSizeToOcr

        public void setMaxFileSizeToOcr​(long maxFileSizeToOcr)
      • getMaxFileSizeToOcr

        public long getMaxFileSizeToOcr()
      • setMinFileSizeToOcr

        public void setMinFileSizeToOcr​(long minFileSizeToOcr)
      • getMinFileSizeToOcr

        public long getMinFileSizeToOcr()
      • setTimeout

        public void setTimeout​(int timeout)
        Set default timeout in seconds. This can be overridden per parse with TikaTaskTimeout sent in via the ParseContext at parse time.
        timeout -
      • getTimeout

        public int getTimeout()
      • setOutputType

        public void setOutputType​(String outputType)
      • getOutputType

        public String getOutputType()
      • setPreserveInterwordSpacing

        public void setPreserveInterwordSpacing​(boolean preserveInterwordSpacing)
      • isPreserveInterwordSpacing

        public boolean isPreserveInterwordSpacing()
      • setEnableImagePreprocessing

        public void setEnableImagePreprocessing​(boolean enableImagePreprocessing)
      • isEnableImagePreprocessing

        public boolean isEnableImagePreprocessing()
      • setDensity

        public void setDensity​(int density)
      • getDensity

        public int getDensity()
      • setDepth

        public void setDepth​(int depth)
      • getDepth

        public int getDepth()
      • setColorspace

        public void setColorspace​(String colorspace)
      • getColorspace

        public String getColorspace()
      • setFilter

        public void setFilter​(String filter)
      • getFilter

        public String getFilter()
      • setResize

        public void setResize​(int resize)
      • getResize

        public int getResize()
      • setApplyRotation

        public void setApplyRotation​(boolean applyRotation)
      • isApplyRotation

        public boolean isApplyRotation()
      • setPreloadLangs

        public void setPreloadLangs​(boolean preloadLangs)
        If set to true and if tesseract is found, this will load the langs that result from --list-langs. At parse time, the parser will verify that tesseract has the requested lang available.

        If set to false (the default) and tesseract is found, if a user requests a language that tesseract does not have data for, a TikaException will be thrown with tesseract's native exception message, which is a bit less readable.

        preloadLangs -
      • isPreloadLangs

        public boolean isPreloadLangs()